In the preparation of the benzoic acid ( pKa 4.2) and in order to precipitate all of the benzoic acid from it sodium benzoate salt in an aqueous solution, students are advised to bring the pH of the solution to less than pH 2 by adding concentrate HCl to the benzoate salt. The following equilibrium shows dissociation of benzoic acid in the aqueous solution. Calculate and explain why pH less than 2 has been suggested. (Hint: First calculate the pH of the benzoic solution at equilibrium) 10. OH

In the preparation of the benzoic acid ( pKa 4.2) and in order to precipitate all of the benzoic acid from it sodium benzoate salt in an aqueous solution, students are advised to bring the pH of the solution to less than pH 2 by adding concentrate HCl to the benzoate salt. The following equilibrium shows dissociation of benzoic acid in the aqueous solution. Calculate and explain why pH less than 2 has been suggested. (Hint: First calculate the pH of the benzoic solution at equilibrium) 10. OH

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter13: Titrations In Analytical Chemistry

Section: Chapter Questions

Problem 13.5QAP

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